Overload regulator for lever hoists

ABSTRACT

A regulator to limit the raising, pulling, or stretching load capacity of a lever type hoist to a predetermined maximum. The regulator is operably mounted between the drive input applied via an operating lever and the output drive on which a load is received and/or contained. An adjustably presettable braking friction applied between coaxially interfit components rotationally connects the input and output drives. In the event the input driving force exceeds the imposed braking friction, the hoist is rendered inoperable to raise, pull or stretch the load but continues operable to lower or release the load.

United States Patent 1 Eggleton, Jr. et al.

[ Dec.4,1973

[ OVERLOAD REGULATOR FOR LEVER HOISTS [75] Inventors: Cecil Howard Eggleton, Jr.,

Fruitport; William Franklin Henry, Muskegon, both of Mich.

[52] US. Cl 254/167, 188/325, 64/30 R [51] Int. Cl B66d 3/14 [58] Field of Search 254/167, 169, 186 l-lC,

[56] References Cited UNITED STATES PATENTS 1,373,810 4/1921 Hansen 64/30 C 1,554,755 9/1925 Parsons 64/30 E 1,561,506 11/1925 Chilton 64/30 E X 1,601,438 9/1926 Gustafson 64/30 E 2,793,515 5/1957 l-lunstiger et 64/30 C 2,889,075 6/1959 Lupo 64/30 E 7/1962 Stevens 254/167 X 11/1970 Stevens 254/ 169 Primary Examiner-Evon C. Blunk Assistant Examiner--James L. Rowland Attorney-Robert W. Mayer, Thomas P. Hubbard, Jr., Daiel Rubin, Raymond T. Majesko, Roy L. Van Winkle, William E. Johnson, Jr. and Eddie E. Scott 5 7 1 ABSTRACT A regulator to limit the raising, pulling, or stretching load capacity of a lever type hoist to a predetermined maximum. The regulator is operably mounted between the drive input applied via an operating lever and the output drive on which a load is received and- /or contained. An adjustably presettable braking friction applied between coaxially interfit components rotationally connects the input and output drives. in the event the input driving force exceeds the imposed braking friction, the hoist is rendered inoperable to raise, pull or stretch the load but continues operable to lower or release the load.

. 20 Claims, 13 Drawing Figures PAIENIEDBEB 1 SHEET 1 0r 4 CECIL H. EGGLETON, JR.

WILLIAM F. HENRY INVENTORE BY M ATTORNEY PAIENTEDHEB 41m 3.776.514

suwaorg 05cm H. EGGLETON, JR. WILLIAM F. HENRY i INVENTORS 4 J h 7 BY ATTORNEY PATENTED DEC 4 I975 sum 3 or 4 F/G. a

CECQIL H. EGGLETON, JR. WILLIAM F. HENRY VENTORZE BY I ATTORNEY OVERLOAD REGULATOR FOR LEVER HOISTS BACKGROUND OF THE INVENTION The field of art to which the invention pertains generally includes the art of article handling as specifically directed to hoisting, pulling, or stretching equipment having a torque limiting clutch mechanism for overload prevention.

Hoists, and in particular hoists hand operated by means of a chain or ratchet lever for elevating or hauling articles or other similar type loads are extensively employed in many applications of industrial life. Noteworthy users are the chemical companies, the automotive companies, shipyards and others having operations requiring frequent hoisting, hauling, or moving of parts, cargo or the like. Each hoist when sold is built to a manufacturers specification for a rated load capacity within which the hoist is capable of being safely operated. When rated capacities are observed and the hoists are otherwise maintained they can be expected to provide many years of trouble free life. However, despite the usual conspicuous display of rated capacity it is common practice among hoist operators to generally ignore the rating and determine hoist input capacity solely by the hoist ability to operate with a particular load. Where the hoist is employed for pulling or stretching, as opposed to mere raising of the load, it is most difficult for the operator to accurately predict the magnitude of load likely to be encountered. Consequently, in either instance the actual load to be encountered is not prejudged and it is not uncommon for the operator to judge safe operating capacity purely on the basis of whether the hoist can tolerate the load without apparent failure. In the case of hand-operated hoists, the input driving force is limited only by the operators physical strength which, via the mechanical leverage provided by the chain or ratchet lever, permits misjudgment substantially greater than intended by the manufacturer. While most marketed hoists have built-in safety factors permitting occasional and moderate exceeding of rated capacities without eqipment damage, it is both economically impractical and impossible for the manufacturer to design a hoist in anticipation of every field condition to which the hoist will likely be subjected.

Hoist failure can of course result in load drop or release and consequent damage not least of which is personal injury or loss of life. Hoist failure from an inability to function at the onset of applied load, e.g. elevate a load from the ground, produces minimal injury in that failure is immediately apparent to the operator and no load drop occurs. What frequently happens however to these hoists is a form of progressive failure from frequent overloading permitting an actual failure from a load even within rated hoist capacity. It can be well appreciated that this latter situation presents a real legal dilemma for the hoist manufacturer in determination of product liability.

Therefore despite long recognition of the overload problem, hoist manufacturers have not heretofore been practically able to protect their equipment and consequently themselves from the after sale abuse inflicted by their customers. Various techniques toward resolving this difficulty have been tried including the obvious of providing a tension scale on the load or output side of the hoist permitting preload determination by the operator. It has been found however that such scales are either ignored or not serviceably maintained, so that overloading continues unchecked and notwithstanding. A regulator particularly suitable for use with chain block hoists is disclosed in US. Pat. No. 3,542,341. A similar purpose regulator more amenable to use with hand lever hoists has not heretofore been available.

SUMMARY This invention relates to a regulator for hoists and particularly to regulators for hand lever hoists to han dle loads of various capacities on the order of l to 6 tons. More specifically, the invention relates to lever hoists having a load regulator whereby negligent operation of the hoist by input overloading in excess of predetermined limits over rated hoist capacity is substantially prevented. Consequently, a greater degree of legal protection after sale of the equipment is afforded a manufacturer by preventing this form of equipment abuse under field conditions otherwise beyond the manufacturers control. Not only does a hoist having a regulator in accordance with invention hereof minimize the possibility of overload within prescribed limits, but moderately incurred overload conditions will not result in load drop or release with consequent damage or personal injury. Moreover, despite moderate overload condition, a hoist when constructed with the regulator hereof continues operable for lowering or releasing the load to, for example, ground or other safe level whereat the excess load can be removed. In accordance with the invention these results are obtained by an adjustably presettable braking friction applied between coaxially interfit components rotationally connecting the input and output drives of the hoist.

It is therefore an object of the invention to provide a novel load regulator for a hoist inherently capable of controlling operating overload.

It is a further object of the invention to provide a novel hoist for raising, pulling or stretching a load having a contained load regulator for preventing input overload abuse thereof.

It is a further object of the invention to provide a regulator for a hand-operated hoist in accordance with the aforesaid objects capable of presettable adjustment to match a wide range of hoist capacities at or near which it is desired to limit operating load capacities.

It is a further object of the invention to provide a hoist regulator in accordance with the aforesaid objects particularly adapted for hand lever operation and in which a sensual signal in the form of lever slippage without load release is emitted to the operator at the time an input overload is incurred.

It is a still further object of the invention to provide an effective hoist regulator economically compatible with hoists of relatively inexpensive construction as to not be cost restrictive and yet be available for a wide range of operating capacities.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an isometric view partially in section of a lever type hoist incorporating a first embodiment regulator assembly in accordance herewith;

FIG. 2 is an axial elevation partially in section through the regulator assembly in the hoist of FIG. 1;

FIG. 3 is an enlarged fragmentary section within the encircled portion of FIG. 2;

FIG. 4 is a sectional elevation as viewed substantially along the lines 44 of FIG. 2;

FIG. 5 is an axial elevation partially in section of the regulator assembly;

FIG. 6 is a left end elevation of the regulator assembly as viewed substantially along the lines 6-6 of FIG.

FIG. 7 is a sectional elevation as viewed substantially along the lines 77 of FIG. 5;

FIG. 8 is a right end elevation taken substantially along the lines 88 of FIG. 5;

FIG. 9 is an axial elevation partially in section of a lever type hoist incorporating a second embodiment regulator assembly in accordance herewith;

FIG. 10 is an axial elevation partially in section through the regulator assembly in the hoist of FIG. 9;

FIG. 11 is a left end elevation of the regulator assembly as viewed substantially along the lines 1111 of FIG. 10;

FIG. 12 is a right end elevation of the regulator assembly as viewed substantially along the lines 12l2 of FIG. 10; and

FIG. 13 is an enlarged fragmentary section of the encircled portion of FIG. 10.

The regulator of the invention will now be described with reference to the drawings in connection with a hoist, which for sake of explanation, is operative for raising and lowering of loads. It is to be understood however, that such use is not intended as a limitation of the invention and that hoists of this type are commonly used for pulling or stretching loads as previously mentioned. Hence, terms hereinafter used such as overhead, downward, and the like shall be construed in that light.

Referring therefore to FIG. 1, there is illustrated a hand operated lever hoist designated 10 incorporating a first regulator embodiment in accordance herewith and generally designated 12. The hoist illustrated is of a type commercially available for rated load capacities on the order of i to 2 ton and is comprised of a generally cylindrical housing 14 from which extends an upstanding hook 15 for mounting the hoist onto a suitable overhead support. Suspended downward from housing 14 is a chain 17 to which at its terminal end there is secured a load hook 18 adapted for receiving a load to be raised or lowered as required. Input for normally operating the hoist either up or down is by means of a handoperated lever 19 which when cranked in a back and forth oscillating motion causes pawl 20 to engage ratchet 21 to in turn rotate hollow output shaft 22 through load brake 23 (FIG. 2) of the commonly used Weston type. Shaft 22 is in turn key connected to a coaxial output drive pinion 24 which translates rotational movement through gearing (not shown) in a conventional manner into a raising or lowering operation of chain 17 and hook 18 secured thereto. Operational direction of the hoist is controlled by a down or up setting of thumb lever 26. Intermediate free setting of thumb lever 26 permits free wheeling of the unloaded chain. While the chain is free wheeled brake 23 is maintained in open position by means of a plunger 31 urged by spring 32 into a detent cavity in brake hub (FIG. 2). Cap screw 33 secures spring 32 in compression against plunger 31.

Reference is now also made to FIGS. 2-8 in which the regulator assembly 12 in accordance with a first embodiment hereof is shown comprised of a ratchet member 21 coaxially enclosing an axial portion of a brake-hub member 30. The brake-hub is helically interfit with knob 27 in turn keyed to shaft 22 by means of key 28 and secured against axially rightward movement thereon by retainer ring 29.

Ratchet member 21 is formed as an annular sleeve or the like 34 of a relatively narrow axial width defined by radial end faces 35 and 36. Between end faces the width is divided into a large diameter on which are exten'orly formed ratchet teeth 37 and a smaller shouldered diameter 38 about which to receive an enclosing portion of lever 19. The sleeve is centrally bored to an internal diameter dimension 39 accurately turned concentric with the outside diameter of teeth 37.

Brake-hub 30 is of an axial width greater than ratchet 21 defined by radial end face 42 and helix end face 43 adapted to cooperate with internal helix 46 of knob 27. The hub supports ratchet 21 and is of an initial outside diameter 44, at least where axially coextensive with ratchet 21, of on the order of a few thousanths less then internal ratchet diameter 39 in order to initially provide rotational freedom therebetween for purposes of assembly. End face 42 terminates in an enlarged annular flange juxtaposed to brake 23 and against which to receive ratchet end face 35.

Approximately midway between hub end faces 42 and 43 and a pair of opposed radial slots 48 and 49 separated from each other and each of about 120 degree angular extent. Laterally communicating with these latter slots leftward as viewed in the figures, is a pair of diametrically opposite axial slots 50 and 51 radially extending between internal diameter surface 52 and the outside diameters of 44 and 45. Formed in opposite faces of the latter axial slots where proximate with radial slots 48 and 49 is a cupped recess enlargement 54 in which to snuggly receive a hardened stainless steel ball 55. Extending axially opposite and radially coincident with each of slot recesses 54 are lateral tapped apertures and 61 opposite slits 50 and 51 respectively.

Received in each of apertures 60 and 61 is an elongated adjustment screw 62 which at its inward end terminates in a conically recessed cup 63 for engagement against ball 55. As will be further explained below, tightened advancement of screw 62 against ball 55 forces the ball thereat against tapered sides of recess 54 to circumferentially spread axial slots 50 and 51. Spreading the latter slots radially expands hub diameter 44 into a predetermined frictional braking engagement against internal ratchet surface 39. The magnitude of frictional engagement can thereby be adjustably preset as required. For these purposes, surface 39 is preferably of a hard smooth finish as of hard chrome plate to which a thin film of lubricant has been applied. I-lub surface 44 is likewise machine smooth of good bearing material such as alloy bronze or the like.

The second regulator embodiment in accordance herewith will now be described with particular reference to FIGS. 9-13. In this embodiment regulator 112 is described for sake of explanation, in conjunction with a hoist which, may for example, be of a type disclosed in US. Pat. No. 3,047,] 14 incorporated herein by reference, and which is generally suitable for greater loads than that which can be accommodated by hoist 10. Regulator 1 12, as in the previous embodiment, is enclosed within lever 119 and is normally effective when actuated by the lever and pawl 120 to rotate output shaft 122 for raising and lowering of load hook 118. For accommodating a Weston type brake in a hoist of the higher capacities, shaft 122 includes an Acme brake thread 123 and is splined at 124 for receiving free wheeling knob 127. Thumb lever 126, by its appropriate setting, controls whether lever 119 when cranked will raise or lower hook 118 or permit free wheel chain operation.

Regulator 112, like regulator 12, is formed of two components consisting of ratchet member 121 supported on brake-nut member 130. Ratchet member 121 is formed of a ringlike sleeve structure 134 of width defined between radial end faces 135 and 136 having ratchet teeth 137 uniformly contained about its annular periphery. The ratchet is centrally bored to an internal diameter 139 accurately concentric with the circumference of ratchet teeth 137.

Brake-nut 130 is likewise annular of width greater than ratchet 121 defined between radial end faces 142 and 143 and is centrally bored and Acme threaded at 144 to cooperate with Acme thread 123. The axial periphery of brake-nut 130 is stepped from a smaller diameter 146 on which to receive ratchet 121 to a shoulder 147 connected with larger diameter 148. Similarly, as in the previous embodiment, the outside diameter 146 is initially of a few thousanths less than internal ratchet diameter 139 in order to initially provide rotational freedom therebetween. Formed as to circumferentially split the ring is radial slot 150 axially extending between end faces 142 and 143 in turn centrally bored and tapped at 151 and square counter slotted at 152. Contained within counterslot 152 is a square insert 153 threaded to receive the threaded end of tapered-head adjusting screw 154.

Advancing the screw inwardly of the insert causes the tapered screw head to advance inwardly of bore 151 forcing a circumferential separation of slot 150. This in turn causes hub diameter 146 to enlarge against the intemal ratchet diameter 139. Radial slits 157 and 158 accommodate the diametral enlargement. As before, hub enlargement is continued until a predetermined rotational braking friction is established between hub 130 and ratchet 121.

A free wheel plunger housing 160 secured to face 136 of the housingpermits free wheeling of knob 127 in a manner similar to that described in connection with knob 27 in the previous embodiment.

During manufacture, each of the regulators are assembled on a suitable fixture fitted with proper measuring equipment. Thereafter either adjustment screw 62 or 154 as the case may be, is tightened down until diametrically expanding the brake hub into a predetermined rotational friction braking engagement with the centrally internal ratchet diameter which surrounds it. The force magnitude of radial braking engagement is determined by the load capacity of hoist with which the regulator is employed and the relative load level corresponding to or slightly above rated load capacity at which further loading of the hoist is to be prevented. In this manner, raising a load at capacities below the adjusted setting level of the regulator effects conjoint operation in unison between the brake hub and ratchet such that the hoist for all practical purposes operates in the manner of such hoists in the prior art. On a load capacity being applied to the load hook exceeding the set level of rotational friction imposed between the brake hub and ratchet, frictional slippage occurs therebetween such that further hoist operation for the purpose of raising a load is prevented. During the latter condition, any cranking motion of the operating lever will merely effect ratchet rotation frictionally independent of the brake hub and drive shaft contained coaxially therein. At the same time while raising of a load is being prevented, operation of the hoist brake mechanism remains in tact in the manner of the prior art as to become operative and prevent a load from dropping. While the latter condition exists the operating lever continues to require substantial amount of force to effect ratchet rotation such that should an operator be partially supporting himself on the lever, support will not suddenly or dangerously be removed. Moreover, by virtue of the braking mechanism in combination with the regulator, lowering a load is effected similarly as in the prior art and which for the second embodiment hereof the brake mechanism is fully disclosed in US.

Pat. No. 3,047,114 supra.

By the above description there is disclosed a novel regulator for hoists by which input overloading of the hoist beyond permissable limits is prevented. When such overload condition is reached motion of the operating lever occurs without motion of the engaged load and is immediately sensed by the operator as indicating existence of an overload condition. At the same time and despite existence of an overload condition, the hoist continues operable for the purpose of lowering a suspended load while braking the load against falling is maintained independent of the regulator device. A lever hoist having a regulator in accordance herewith is highly effective in achieving a greater degree of protection long sought by manufacturers of lever hoists yet retaining the desirable braking feature commonly contained in hoists previously marketed. Thus, by the simple relative uncostly addition to a hoist of a regulator essentially in the form of a friction clutch, the invention hereof has solved a longstanding need which has plagued the industry for many years.

Since many changes could be made in the above construction and many apparently widely different embodiments of this invention could be made without departing from the scope thereof, it is intended that all matter contained in the drawings and specification shall be interpreted as illustrative and not in a limiting sense.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. In a hoist for drawing and releasing of loads having an output extension on which to receive a load, and input drive means responsive to a correlated directional input thereto for operably controlling the drawing and releasing of said output extension, a regulator for limiting load drawing capacity of the hoist and comprising:

a. a first rotatable section connected to said input drive means for rotational movement therewith;

b. a second rotatable section coaxially superposed to said first rotatable section and connected to said output extension for rotational movement therewith;

. said first and second sections being arranged coaxially interfit one within the other with at least an axial portion of an outside diametral surface of the inner section adapted to be in frictional engagement with at least an axial portion of the internal diametral surface of the outer section and with the inner of said sections including at least one radial slot of predetermined axial extent having locally tapered surfaces in opposite walls at an intermediate location defining a locally enlarged recess therewithin;

d. substantially inelastic sphere means contained within said slot recess; and

e. presettable screw adjustment means for effecting a rotational braking friction between said first and second rotatable sections to provide a predetermined degree of limited braking therebetween correlated to a value of load at which the hoist capacity is to be limited;

f. said screw adjustment means including a screw threadedly supported in the wall of said inner section in axial alignment with the sphere means in said slot recess, the inward end of said screw being effective when operatively advanced in engagement against said sphere means for said sphere means to spread said slot increasing the outer diametral surface of said inner section against the inner diametral surface of said outer section.

2. In a hoist according to claim 1 in which said first rotatable section comprises said inner section and said second rotatable section comprises said outer section.

3. In a hoist according to claim 1 in which said inner section includes a plurality of said at least one radial slot displaced about the periphery each containing sphere means in the recess thereof and there is included a plurality of said screw adjustment means of like quantity as said slot plurality aligned in a one for one arrangement.

4. In a hoist according to claim 3 in which the inward end of said screw means is conically recessed.

5. In a hoist for drawing and releasing of loads having an output extension on which to receive a load, and input drive means responsive to a correlated directional input thereto for operably controlling the drawing and releasing of said output extension, a regulator for limiting load drawing capacity of the hoist and comprising:

a. a first rotatable section connected to said input drive means for rotational movement therewith;

b. a second rotatable section coaxially superposed to said first rotatable section and connected to said output extension for rotational movement therewith;

said first and second sections being arranged coaxially interfit one within the other with at least an axial portion of an outside diametral surface of the inner section adapted to be in frictional engagement with at least an axial portion of the internal diametral surface of the outer section and with the inner of said sections including at least one pair of spaced apart walls defining a radial slot of predetermined axial extent; and

d. presettable screw adjustment means for effecting a rotational braking friction between said first and second rotatable sections to provide a predetermined degree of limited braking therebetween correlated to a value of load at, which the hoist capacity is to be limited; said screw adjustment means including means having an axially tapered portion axially advanceable within said slot to efi'ect controlled spreading of said slot walls.

6. In a hoist according to claim 5 in which said screw adjustment means comprises a screw and a nut coupled from opposite ends of said slot and one of which has an axially tapered portion to advance inwardly of said slot in response to a tightened force applied to said screw.

7. In a hoist according to claim 6 in which said axially tapered portion is contained on the head of said screw.

8. In a hoist for drawing and releasing of loads comprising:

a. a lever operable when actuated to effect drawing and releasing of loads;

b. input means operably connected to said lever for transmitting the appropriate draw or release drive input thereof;

c. output means on which to receive a load to be drawn or released by actuation of said lever;

d. a regulator for limiting load drawing capacity of the hoist including:

1. a first rotatable section connected to said input means for rotational movement therewith;

2. a second rotatable section coaxially superposed to said first rotatable section and connected to said output means for rotational movement therewith; and

3. adjustably presettable means for effecting a rotational braking friction between said first and second rotatable sections to provide a predetermined degree of limited braking therebetween correlated to a value of load at which the hoist capacity is to be limited; and

e. second braking means operative independent of said lever for controlling the release rate of a load received on said output means.

9. In a hoist according to claim 8 in which said first and second regulator sections are arranged coaxially interfit one within the other and at least an axial portion of an outside diametral surface of the inner section is in frictional engagement with at least an axial portion of the internal diametral surface of the outer section.

10. In a hoist according to claim 9 in which said first rotatable section comprises said inner section and said second rotatable section comprises said outer section.

11. In a hoist according to claim 9 in which said adjustable presettable regulator means comprises means for diametrically urging at least one of said diametral surfaces toward the other until achieving a desired predetermined degree of limited frictional braking therebetween.

12. In a hoist according to claim 11 in which said adjustable presettable regulator means comprises screw actuated means operative when advanced in a tightening direction to effect said urging between said diametral surfaces.

13. In a hoist according to claim 12 in which said screw actuated means is contained within the inner of said first and second regulator sections and is operative when advanced to effect said urging by enlarging said outer diametral surface of said inner section toward said inner diametral surface of said outer section.

14. In a hoist according to claim 13 in which said inner regulator section contains means defining at least one radial slot of predetermined axial extent receiving the operative effect of said screw means to increasingly spread apart in response to screwed advancement thereof. 4

15. In a hoist according to claim 14 inwhich said de fined regulator slot includes a locally enlarged recess at an intermediate location extending into the opposing walls thereof, and sphere means within said recess being engaged by the inward end of said screw means, said screw means being arranged extending axially into said slot radially coincident with said sphere means for applying a force thereagainst to effect controlled spreading of said slot walls.

16. In a hoist according to claim in which said inner section includes a plurality of said at least one radial slot displaced about the periphery each containing sphere means in the recess thereof and there is included a plurality of said screw means of like quantity as said slot plurality aligned in a one for one arrangement.

17. In a hoist according to claim 16 in which the inward end of said screw means is conically recessed.

18. In a hoist according to claim 14 in which said regulator screw means includes means having an axially tapered portion axially advancable within said slot to effect controlled spreading of said slot walls.

19. In a hoist according to claim 18 in which said regulator screw means comprises a screw and a nut coupled from opposite ends of said slot and one of which has an axially tapered portion to advance inwardly of said slot in response to a tightening force applied to said screw.

20. In a hoist according to claim 19 in which said axially tapered portion is contained on the head of said 

1. In a hoist for drawing and releasing of loads having an output extension on which to receive a load, and input drive means responsive to a correlated directional input thereto for operably controlling the drawing and releasing of said output extension, a regulator for limiting load drawing capacity of the hoist and comprising: a. a first rotatable section connected to said input drive means for rotational movement therewith; b. a second rotatable section coaxially superposed to said first rotatable section and connected to said output extension for rotational movement therewith; c. said first and second sections being arranged coaxially interfit one within the other with at least an axial portion of an outside diametral surface of the inner section adapted to be in frictional engagement with at least an axial portion of the internal diametral surface of the outer section and with the inner of said sections including at least one radial slot of predetermined axial extent having locally tapered surfaces in opposite walls at an intermediate location defining a locally enlarged recess therewithin; d. substantially inelastic sphere means contained within said slot recess; and e. presettable screw adjustment means for effecting a rotational braking friction between said first and second rotatable sections to provide a predetermined degree of limited braking therebetween correlated to a value of load at which the hoist capacity is to be limited; f. said screw adjustment means including a screw threadedly supported in the wall of said inner section in axial alignment with the sphere means in said slot recess, the inward end of said screw being effective when operatively advanced in engagement against said sphere means for said sphere means to spread said slot increasing the outer diametral surface of said inner section against the inner diametral surface of said outer section.
 2. In a hoist according to claim 1 in which said first rotatable section comprises said inner section and said second rotatable section comprises said outer section.
 2. a second rotatable section coaxially superposed to said first rotatable section and connected to said output means for rotational movement therewith; and
 3. adjustably presettable means for effecting a rotational braking friction between said first and second rotatable sections to provide a predetermined degree of limited braking therebetween correlated to a value of load at which the hoist capacity is to be limited; and e. second braking means operative independent of said lever for controlling the release rate of a load received on said output means.
 3. In a hoist according to claim 1 in which said inner section includes a plurality of said at least one radial slot displaced about the periphery each containing sphere means in the recess thereof and there is included a plurality of said screw adjustment means of like quantity as said slot plurality aligned in a one for one arrangement.
 4. In a hoist according to claim 3 in which the inward end of said screw means is conically recessed.
 5. In a hoist for drawing and releasing of loads having an output extension on which to receive a load, and input drive means responsive to a correlated directional input thereto for operably controlling the drawing and releasing of said output extension, a regulator for limiting load drawing capacity of the hoist and comprising: a. a first rotatable section cOnnected to said input drive means for rotational movement therewith; b. a second rotatable section coaxially superposed to said first rotatable section and connected to said output extension for rotational movement therewith; c. said first and second sections being arranged coaxially interfit one within the other with at least an axial portion of an outside diametral surface of the inner section adapted to be in frictional engagement with at least an axial portion of the internal diametral surface of the outer section and with the inner of said sections including at least one pair of spaced apart walls defining a radial slot of predetermined axial extent; and d. presettable screw adjustment means for effecting a rotational braking friction between said first and second rotatable sections to provide a predetermined degree of limited braking therebetween correlated to a value of load at which the hoist capacity is to be limited; said screw adjustment means including means having an axially tapered portion axially advanceable within said slot to effect controlled spreading of said slot walls.
 6. In a hoist according to claim 5 in which said screw adjustment means comprises a screw and a nut coupled from opposite ends of said slot and one of which has an axially tapered portion to advance inwardly of said slot in response to a tightened force applied to said screw.
 7. In a hoist according to claim 6 in which said axially tapered portion is contained on the head of said screw.
 8. In a hoist for drawing and releasing of loads comprising: a. a lever operable when actuated to effect drawing and releasing of loads; b. input means operably connected to said lever for transmitting the appropriate draw or release drive input thereof; c. output means on which to receive a load to be drawn or released by actuation of said lever; d. a regulator for limiting load drawing capacity of the hoist including:
 9. In a hoist according to claim 8 in which said first and second regulator sections are arranged coaxially interfit one within the other and at least an axial portion of an outside diametral surface of the inner section is in frictional engagement with at least an axial portion of the internal diametral surface of the outer section.
 10. In a hoist according to claim 9 in which said first rotatable section comprises said inner section and said second rotatable section comprises said outer section.
 11. In a hoist according to claim 9 in which said adjustable presettable regulator means comprises means for diametrically urging at least one of said diametral surfaces toward the other until achieving a desired predetermined degree of limited frictional braking therebetween.
 12. In a hoist according to claim 11 in which said adjustable presettable regulator means comprises screw actuated means operative when advanced in a tightening direction to effect said urging between said diametral surfaces.
 13. In a hoist according to claim 12 in which said screw actuated means is contained within the inner of said first and second regulator sections and is operative when advanced to effect said urging by enlarging said outer diametral surface of said inner section toward said inner diametral surface of said outer section.
 14. In a hoist according to claim 13 in which said inner regUlator section contains means defining at least one radial slot of predetermined axial extent receiving the operative effect of said screw means to increasingly spread apart in response to screwed advancement thereof.
 15. In a hoist according to claim 14 in which said defined regulator slot includes a locally enlarged recess at an intermediate location extending into the opposing walls thereof, and sphere means within said recess being engaged by the inward end of said screw means, said screw means being arranged extending axially into said slot radially coincident with said sphere means for applying a force thereagainst to effect controlled spreading of said slot walls.
 16. In a hoist according to claim 15 in which said inner section includes a plurality of said at least one radial slot displaced about the periphery each containing sphere means in the recess thereof and there is included a plurality of said screw means of like quantity as said slot plurality aligned in a one for one arrangement.
 17. In a hoist according to claim 16 in which the inward end of said screw means is conically recessed.
 18. In a hoist according to claim 14 in which said regulator screw means includes means having an axially tapered portion axially advancable within said slot to effect controlled spreading of said slot walls.
 19. In a hoist according to claim 18 in which said regulator screw means comprises a screw and a nut coupled from opposite ends of said slot and one of which has an axially tapered portion to advance inwardly of said slot in response to a tightening force applied to said screw.
 20. In a hoist according to claim 19 in which said axially tapered portion is contained on the head of said screw. 